Industrial parks have shown an important development trend of employing distributed generations instead of traditional centralized power supply. This paper studies the planning method of power supply systems in industrial parks, considering demand side response based on day‐ahead real time pricing. An improved demand side response model is proposed to solve the imbalance of energy shifting and overwork of demand side response when price elasticity matrix is used. Furthermore, an optimal planning model is established, taking minimum total cost as the optimization objective, and solved by the GA‐PS algorithm. Additionally, two indexes, the ratio of distributed generation deficiency energy and the ratio of distributed generation deficiency hours, are proposed to characterize the complementary of multi‐energy. Finally, a case of a typical power supply system in an industrial park is given to validate the proposed method.
The reliability evaluation of distribution network is an important part of power system. In the extreme situation caused by aging or weather, the multi-fault affect the distribution network reliability. There are only few reliability assessment approach considered the impact of multi-faults. It’s necessary to have a method that can ensure both accuracy and efficiency. The impact increment method based on Monte Carlo sampling (IIMC) can meet the requirements in transmission network. After improving the independent faults identification by distribution network structure, the RBTS Bus6 system is used as an example to test the effectiveness of IIMC. Compared with traditional Monte Carlo sampling. When the failure rate of components is high for the aging and other reasons, the result can show the advantage of IIMC.
Plug-in hybrid electric bus (PHEB) have more potential fuel efficiency than traditional hybrid electric vehicle (HEV) . For rule-based energy management, the fuel consumption can be significantly influenced by vehicle architectures and driving condition. Firstly, a specific PHEB transmission configuration utilizing two planetary gear sets was determined for urban road conditions, and different driving modes have been divided by controlling the clutch state. A PHEB model is built by MATLAB/Simulink in accordance with rule-based strategy characterized as a flow chart. Simulation results on china city bus cycle (CCBC) show that fuel economy (13.90 L/100km) still have room for improvement compared with dynamic programming (DP) based energy management strategy (EMS).
1D modelling for micro gas turbines (MGTs) is a major area of interest in the field of distributed multigeneration. In this paper a 1D simulation model for a commercialised MGT has been developed and validated against the manufacturer data using SimcenterAmesim. The developed model is a primarily tool to address the operational challenges of MGT, investigate future fuelling and investigate its integration with other energy storage / conversion systems. At this stage of research, the agility of the developed model is demonstrated by carrying out a parametric study to investigate the effect of varying the compressor inlet temperature on the overall system performance. Itwas revealed that the air mass flow rate was very sensitive to compressor inlet temperature change. Varying the compressor inlet temperature from 278K to 308K showed an increase of systemefficiency by 1.2%.
A numerical analysis of heat and mass transfer in an indirect evaporative cooling system for building applications is presented. The model is based on the computational fluid dynamics software CFX-4 and makes use of the built-in Spray Drier model to study the droplet movement, heat transfer, and evaporation rate from the water to the exhaust air. The effect of the average droplet size and mass flow rate as well as the angle of the heat exchanger on the cooling performance to the supply air is reported.
The purpose of this study is to understand the effect of an over-estimated cooling set-point temperature (28°C) on work productivity in Korea’s public buildings during the summer season. Two experiments were conducted. The first experiment aimed at measuring work performance through typing and cognitive tests and detecting work stress using an electroencephalogram at 28°C. The second experiment was conducted at 24°C with the same contents as the first. The results showed that a cooling set-point temperature of “28°C” brings benefits in terms of energy consumption, but it drops work performance, thereby having an adverse effect on overall productivity.
Static synchronous compensator (STATCOM) can effectively improve the power quality in the mediumvoltage distributed energy system (DES). In order to keep the system stable operation, fault-tolerant ability should be maintained to improve the reliability of STATCOM. With the idea of virtual capacitor voltage, a simplified fault-tolerant control scheme is proposed for popular cascaded H-bridge (CHB) based STATCOM. First, an improved modulation method is adopted to significantly reduce these carrier waves. Then, based on the virtual capacitor voltage, the control scheme during the cell fault can be further simplified. Finally, the detailed postfault operation principle is presented according to different operation conditions of STATCOM, where the capacitor voltages in the faulty phase can remain unchanged in certain cases. Validation results verify the effectiveness of the proposed fault-tolerant scheme.
With the increase of residential energy consumption, its proportion in primary energy consumption is higher and higher. Accurate prediction of residential electricity consumption is the premise of rational residential energy management. In this paper, a novel multi-step prediction model using particle swarm optimization (PSO), Holt-Winter (HW) method, and extreme learning machine (ELM) network is proposed for forecasting household power consumption. The HW model optimized by PSO is the main predictor and used to deal with the periodicity and seasonality of household electricity load. ELM model is introduced as the correction predictor to predict the prediction error of HW, so as to improve the prediction accuracy. The experimental results show that the PSO-HW-ELM model has higher prediction accuracy and better stability compared with the single HW and ELM model.
This paper presents a power management strategy to control a DC microgrid considering the operation in the grid connected mode. The analyzed system is composed of the utility grid interfaced with a voltage source converter, an energy storage system (ESS), a distributed generator and the customer loads. The proposed power management is considered as a master-slave technique, in which the VSC operates as a master grid-forming converter, while the ESS is a slave grid- supporting unity and the distributed generator works as a grid-feeding unity tracking the maximum power point. This management strategy is presented in details and its impact over the DC link voltage, the power flow and the ESS state of charge is analyzed. MATLAB/Simulink simulations are performed to obtain the results. The obtained results show that the proposed strategy is reliable and leads to better controllability over the power flow in the DC microgrid when compared with the hierarchical control.
This paper presented a torque distribution strategy based on linear time-varying quadratic programming (LTV-QP) for yaw stability control of all-wheelindependent- drive electric vehicles. A two-degree-offreedom vehicle dynamic model was established to figure out the desired vehicle states including sideslip angle of the centroid of vehicle and the yaw moment, which was used as the reference signal of the LTV-QP controller. However, the influence of the time-varying steering angle was generally not taken into account. A QP-based torque distribution strategy is put forward to reduce the yaw rate error caused by them. The proposed strategy is evaluated in Matlab/Simulink to track the reference yaw moment and optimize the torque distribution. The results indicate that the LTV-QP controller can effectively distribute the torques of four in-wheel motors and significantly improve the vehicle yaw stability.